Synthesis, characterization, and degradation of poly(ethylene‐ b ‐ ε ‐caprolactone) diblock copolymer

Poly(ethylene‐ b ‐ ε ‐caprolactone) (PE‐ b ‐PCL) diblock copolymers were synthesized by ring‐opening polymerization (ROP) of ε ‐caprolactone (CL) with α ‐hydroxyl‐ ω ‐methyl polyethylene (PE‐OH) as a macroinitiator and ammonium decamolybdate (NH 4 ) 8 [Mo 10 O 34 ] as a catalyst. Polymerization was conducted in bulk (130–150°C) with high yield (87–97%). Block copolymers with different compositions were obtained and characterized by 1 H and 13 C NMR, MALDI‐TOF, SAXS, and DSC. End‐group analysis by NMR and MALDI‐TOF indicates the formation of α ‐hydroxyl‐ ω ‐methyl PE‐ b ‐PCL. The PE‐ b ‐PCL degradation was studied using thermogravimetric analysis (TGA) and alkaline hydrolysis. The PCL block was hydrolyzed by NaOH (4M), without any effect on the PE segment. Copyright © 2009 John Wiley & Sons, Ltd.